Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
433 PM EDT Sun Mar 26 2023
Valid 12Z Thu Mar 30 2023 - 12Z Mon Apr 03 2023
...Overview/Guidance Evaluation/Predictability Assessment...
A progressive flow pattern is expected across portions of Alaska
during the forecast period, except near the Western Aleutians,
where a deep layer cyclone should be relatively stuck for much of
the period. Periods of unsettled weather, particularly rain/snow,
is most favored across the southern/coastal sections of the state.
In general, the synoptic pattern was better clustered than usual.
For the pressures, winds, 500 hPa heights, and QPF, used a
compromise of the 12z UKMET, 12z GFS, 12z Canadian, and 12z ECMWF
to help deal with detail uncertainty early on before blending in
the 12z NAEFS and 00z ECMWF ensemble means to deal with lingering
detail issues. The remainder of the grids were based primarily on
the 19z NBM.
...Weather/Hazard Highlights...
Gales are expected across portions of the AK Peninsula and Upper
Aleutians from Thursday into Friday as a cyclone develops in the
northeast Pacific/Gulf of AK. This system will produce
precipitation for south-central AK and the AK panhandle but
amounts should remain modest. As an occluded cyclone and its
associated cold front pass across northern AK, a slow cooling
trend is expected along the North Slope in its wake.
Temperature-wise, it looks coldest across the North Slope, with
temperatures becoming more subzero with time by next weekend.
Milder temperatures are expected across central and southern AK,
with daily maxima above the freezing mark expected in spots across
portions of interior AK.
Roth
WPC medium range Alaskan products including 500mb, surface
fronts/pressures progs and sensible weather grids can also be
found at:
https://www.wpc.ncep.noaa.gov/alaska/ak_5dayfcst500_wbg.gif
https://www.wpc.ncep.noaa.gov/alaska/akmedr.shtml
https://www.wpc.ncep.noaa.gov/alaska/ak_5km_gridsbody.html